The Spectrum of HD 187399.
Abstract
Bright hydrogen lines were discovered at Mount Wilson in 1921. A few slit spectrograms at several observatories showed a considerable difference between the displacements of dark hydrogen lines and those of other elements. The present study with higher dispersion shows that the star is a spectroscopic binary with a period of 28 days and a velocity range of 209 km/sec. There are two sets of dark hydrogen lines, both of variable intensity, one of which usually yields the same velocity as the lines of other elements, while the other has a nearly constant negative displacement. The facts suggest that the binary orbit is enveloped by a cloud of incandescent hydrogen whose outer absorbing layers are rapidly expanding. The system resembles ~3 Lyrae in certain respects
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1949
- DOI:
- 10.1086/145176
- Bibcode:
- 1949ApJ...110...59M